It's because of the spider gears in Diffy. When you turn one rear wheel forward withe the driveshaft held with the Trans mounted parking brake, the other rear wheel will turn backwards. This is why you don't want the rear wheels off the ground on any hill. Actually, any time.
Lostdog/Kittyskeeper, thanks for the explanation. Your theory is sound;however, my unit does experience during leveling, times when just one of the rear wheels maybe slightly off the ground. I spoke with an engineer at Lippert and he advised that the system was designed to operate in those conditions. He did say that you never want BOTH rear wheels off the ground, but one is acceptable. In most cases if I have an off the ground wheel condition it is the front.
If one wheel is off the ground and the MH is on a hill, the MH will go down hill in a circle even with the park brake on.
LOL. Well that is something I would never want to see. I never park on a hill. My issues have all been on fairly level commercial camping sites such as Yogi Bear. But again I have had sites where one of the rear wheels was off the ground. But the coach was completely level.
When you deploy your four point levellers the weight of the chassis is transferred from the wheels, tires ( both front and rear) to the leveller pads which are flat discs. If one or more tire is elevated off the ground to achieve level then what's the big deal? As far as the chassis is concerned level is level, tires do not play a part. True, if you level on the side of a mountain the MH might slide down the hill and possibly bend the levellers but it will not initially roll down the hill. If levelled on very soft ground the leveller pads might dig in but this movement is down not fore or aft and now the leveller pads actually act as anchors restricting all movement, including powered movement if attempted. I'm done.
Bubbles is correct for leveling jacks. I was explaining the process of the differential in relation the the transmission mounted parking brake. GM never, as long as I can remember, has had that type of parking brake. They have always locked both rear wheels for jacking and tire removal. Best to read the Ford owners manual in tire changing.
When you deploy your four point levellers the weight of the chassis is transferred from the wheels, tires ( both front and rear) to the leveller pads which are flat discs. If one or more tire is elevated off the ground to achieve level then what's the big deal? As far as the chassis is concerned level is level, tires do not play a part...
I gave this a lot of thought before making up wooden blocks to put the tires on (for the purpose of "rough-leveling" the coach before deploying the jacks).
I think you are asking "what's the point of leveling the coach with blocks, if you have leveling jacks"? Sorry if I didn't make it clear the first time, but you have to get the coach within about 1.0 to 1.5 degrees of level in order to not get an "excess slope" response from the leveler. And that is after you have done a successful null reset. And don't forget, you want the same number of boards under the jacks as are under the adjacent wheel(s).
I gave this a lot of thought before making up wooden blocks to put the tires on (for the purpose of "rough-leveling" the coach before deploying the jacks).
I think you are asking "what's the point of leveling the coach with blocks, if you have leveling jacks"? Sorry if I didn't make it clear the first time, but you have to get the coach within about 1.0 to 1.5 degrees of level in order to not get an "excess slope" response from the leveler. And that is after you have done a successful null reset. And don't forget, you want the same number of boards under the jacks as are under the adjacent wheel(s).
I have never used blocks nor have I ever received an excessive slope response from the leveler. My unit levels perfectly, even without ever doing a null reset;however, in some cases my wheels still come off the ground. Which after all this research appears to be OK.
OK, so I was at the dealer the other day and observed a customer bring in a 2014 GT XL. His frame was bent and you could easily see that his rear leveling jacks were also bent. After hearing the story it appeared to me that this was a user error; however, it prompted another discussion. The service manager brought up that the GT series should never lift the wheels off the ground when leveling. I advised that on several occasions, even on a level camp site, my unit lifts one or two wheels off the ground. The service advisor advised that the jacks were not made to support the weight of the unit and will bend the frame. I called Lippert, and they said, while it is not what they would want, it is OK for the unit to lift off the ground to creat a level environment. What do you guys think?
We also had a problem with our 2013 Georgetown XL..ours lifted too much on a pretty level spot..it would not then retract. Called for help as we were way off the ground. (Problem solved).. Popped a breaker..this is safety feature so as not to burn up the motor for the leveling system..located under step. Then we found a good level spot and manually leveled it and went thru the ZERO set procedure . We are good now. Sometimes we think we are leveled too high so we will manually set it.
The easy way to level. Buy an inexpensive pair of bubbles, install them next to your controls and level manually. Perfect results every time with wheels on ground.
The reason I bought a Class A was so I could run the air while traveling, pull in, push a button (jacks), push a few more buttons (slides), push a another button (awning) all while being in a nice air conditioned environment. Once my fingers take a good rest, I can then go out and hook up the electric, water and sewer. Sometimes my front tires come off the ground, but never my back. By the way, the Lippert system only allows a certain amount of extension between all the jacks. If you have the front fully extended you can't fully extend the back. Same side to side. Also, if you try to extend the jacks when the RV is too far out of level (not safe) the "Excessive Angle" light will come on and your jacks won't deploy. Keep it easy....push the button.
Not a good idea. You should preferably leave your "nice air conditioned environment" and use pads under the jacks, especially if you're parking on grass or dirt; otherwise, the jacks will just push down into the ground. The pads will also help prevent the jacks from overextending, which I've been told by many people is not a good thing. Some campgrounds even require you to use pads under your jacks to prevent damage to their sites. My jacks work much better when I use the pads, and it's worth a little trip outside (and under) to place the pads.
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Gary Shapiro, 2011 Georgetown 29' Class A
Dash, Molly & Lily - now at the Bridge and forever in my heart
Shadow - 4-year-old Greyhound
Hannah - 1 1/2-year-old GSD rescue
Reset the auto level when the coach is as level as you can get it by using 4 ft level on the floor and counters.
At that time position a small bubble level with it centered so you can see it at the drivers seat.
Drive the coach to a site and move it for the best level.
Place boards under wheels as needed to center the bubble.
Auto level the coach.
You will never be disappointed with the coaches level and stability
The easy way to level. Buy an inexpensive pair of bubbles, install them next to your controls and level manually. Perfect results every time with wheels on ground.
I have the Clinomenter HD "bubble level" app on my iPad, and checked it with a 4-ft carpenters level. The iPad was just as accurate (perfect match), but the readout was more precise than the 4-ft level, i.e. to the nearest 0.1 degree.
We usually have to manually level, as the null reset procedure doesn't seem to do the trick, and our system frequently gives a false "excess slope" error, such when trying to level from less than 1 degree fore/aft, and zero degree tilt. We're going to get this looked at when in Elkhart.
BTW, we use boards under the tires for fore/aft and sideways tilt correction, with the same number under the feet as under the adjacent tire(s). That gets us close enough that "auto-level" usually works.
The boards are an extra chore, but we get no weld stress cracks from overextension, and don't lose traction with tires off the ground. Many folks say they can't see anything wrong with having their wheels off the ground, but I'll bet no one does when next to the South Rim of the Grand Canyon (more Darwinism).
Not a good idea. You should preferably leave your "nice air conditioned environment" and use pads under the jacks, especially if you're parking on grass or dirt; otherwise, the jacks will just push down into the ground. The pads will also help prevent the jacks from overextending, which I've been told by many people is not a good thing. Some campgrounds even require you to use pads under your jacks to prevent damage to their sites. My jacks work much better when I use the pads, and it's worth a little trip outside (and under) to place the pads.
On my 3rd year on a variety of surfaces including grass, asphalt, gravel and concrete. I hear what you are saying, but no problems have been experienced and I'm happy, happy, happy!
I just dropped my Georgetown 360 off at the dealer for some more warranty work, after our last 6,000 mile "excursion". One of the items I noted was the tendency for the Auto Levelers to raise the front wheels "off the ground", almost every time to level the coach. Most of the time it was not necessary. I would get out and look after the system leveled us. The front wheels are in the air, the rear suspension raised, but rear wheels still on the ground. I would go back in, lower the front tires so they touched terra firma, then lower the rear and the coach was still level. (Used a level on the kitchen floor to make sure). My question to him... WHY the height? We'll see what they come up with.
Good Luck with your dealer. When I took mine back with a list just weeks after I got it mine was doing the something. They told me it was not a warranty item. When I expressed surprise he said ok we'll do it. Later after having the batteries disconnected it was off again. By this time I had discovered the reset on the lippert Web site and now it's fine.
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2012 Georgetown 378TS Fire Mist
2008 Honda Fit
ReadyBrake™ Surge Brake System integrated with ReadyBrute™ Elite RV Tow Bar
Protect-A-Tow
Linear Mode
